PHYSIOLOGY OF MOUTH-BREATHING APPLIANCES. 



179 



TABLE 49. Respiratory exchange of E. D. B. in experiments without food for studying effect 

 of long and short duration of preliminary mouthpiece breathing. 1 (Values per minute.) 



! The subject stood continuously or walked continuously in each comparison, i. e., also in the 

 interval between the two tests. Between the comparisons he sat down and rested for approxi- 

 mately 30 to 40 minutes. The time given for the preliminary mouthpiece breathing is approxi- 

 mate. 



2 See table 55, column/, p. 209. 



3 Measurement of oxygen could not be obtained in this period. 



4 In the grade-walking experiments, the grade was 30 p. ct. and the speed averaged 49 meters 

 on March 4, 51 meters on March 6, and 52 meters on March 7 and 8. 



